Fixing UI bug for a new session

tui/app.py

@@ -51,8 +51,7 @@ class HendrikTUI:
         }
 
     def new_session(self):
-        name = f"Session {datetime.now().strftime('%Y-%m-%d %H:%M')}"
-        self.current_session = self.session_mgr.create(name, self._model_info())
+        self.current_session = None
         self.messages = [{"role": "system", "content": self.build_system_prompt(
             tools_definition=self.tools_def,
             character=config.AGENT_CHARACTER or None,
@@ -60,6 +59,9 @@ class HendrikTUI:
         )}]
         self.log.clear()
         self.scroll = 0
+        self.input_buffer = [""]
+        self.input_line = 0
+        self.input_col = 0
         log(self, "welcome", WELCOME_ART)
 
     def switch_session(self, doc_id: int):